Local installation having issues with MS SQL Server

Hey Guys,Sys Admin here, having some trouble getting SuiteCRM to run with MS SQL Server. I have been able to get it running with MySQL successfully with no issue. I cannot seem to get SuiteCRM to connect to MySQL correctly. The MS SQL instance is running locally on the same machine as IIS (Web Server). We are running PHP 5.4.45, and have the appropriate extension attached because the option to select MS SQL is present. The credentials I am providing are correct, as I can login to the database with them, and the IP is set as localhost. What am I missing here?

did you create the db first?